From ccca6607c545534e5b74ef04e0f2f6ba11344be4 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 13 Oct 2016 08:42:17 +0200 Subject: [PATCH] netfilter: nft_range: validate operation netlink attribute Use nft_parse_u32_check() to make sure we don't get a value over the unsigned 8-bit integer. Moreover, make sure this value doesn't go over the two supported range comparison modes. Fixes: 9286c2eb1fda ("netfilter: nft_range: validate operation netlink attribute") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_range.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nft_range.c b/net/netfilter/nft_range.c index c6d5358482d1..9bc4586c3006 100644 --- a/net/netfilter/nft_range.c +++ b/net/netfilter/nft_range.c @@ -59,6 +59,7 @@ static int nft_range_init(const struct nft_ctx *ctx, const struct nft_expr *expr struct nft_range_expr *priv = nft_expr_priv(expr); struct nft_data_desc desc_from, desc_to; int err; + u32 op; err = nft_data_init(NULL, &priv->data_from, sizeof(priv->data_from), &desc_from, tb[NFTA_RANGE_FROM_DATA]); @@ -80,7 +81,20 @@ static int nft_range_init(const struct nft_ctx *ctx, const struct nft_expr *expr if (err < 0) goto err2; - priv->op = ntohl(nla_get_be32(tb[NFTA_RANGE_OP])); + err = nft_parse_u32_check(tb[NFTA_RANGE_OP], U8_MAX, &op); + if (err < 0) + goto err2; + + switch (op) { + case NFT_RANGE_EQ: + case NFT_RANGE_NEQ: + break; + default: + err = -EINVAL; + goto err2; + } + + priv->op = op; priv->len = desc_from.len; return 0; err2: -- 2.20.1